Originally Posted by
FlightDetent
G.rivett: The landscape we are seeing now, to explain the bewilderment,
Lower Vmcg/a does not explain it, because the DRT operates inside its limit and so does the AST.
Hi FlightDetent,
DRT has a lower VMCA / VMCG - hence V1 min (V1 GO) is lower which can be achieved earlier during the take off run. Thus it is possible to increase TO mass despite lower thrust setting. Thrust above DRT is NOT allowed.
FLEX, Assumed Temp etc. may produce the same thrust as DRT - but crews are permitted to to increase thrust up to TOGA limit in the event of an Engine Failure. Therefore VMCG / VMCA must be higher - thus the V1 min must be higher than the V1 min associated with DRT.